2-Nitroanisole. Determining in workplace air with gas chromatography

Abstract

2-Nitroanisole is a colourless or slightly yellowish liquid. This substance is mainly used in the production of o-anisidine (2-methoxyaniline), which is directly or indirectly used for the production of more than 100 azo dyes. 2-Nitroanisole may cause cancer to humans. The aim of this study was to develop a method for determining concentrations of 2-nitroanisole in workplace air in the range from 1/10 to 2 of maximum admissible concentration (MAC) values. The developed method is based on the adsorption of 2-nitroanisole on a silica gel, extraction with methanol and chromatographic analysis of the resulting solution. The tests were performed using a liquid chromatograph (HPLC) 1200 series of Agilent Technologies with a diode array detector (DAD). Determinations were performed using an Ultra C18 column (25 cm × 4.6 mm, dp = 5 µm). The procedure was validated according to Standard No. EN 482. The method can be used to determine 2-nitroanisole in workplace air in the concentration range from 0.16 to 3.2 mg/m3, i.e., from 1/10 to 2 MAC values. In that range, the obtained calibration curve was linear, as evidenced by the regression coefficient of 1. The overall accuracy of the method was about 5.3% and its relative total uncertainty was 23%. This method enables selective determination of 2-nitroanisole in workplace air in the presence of other compounds, such as methanol, o-anisidine, 3-nitroanisole, 4-nitroanisole and 1-chloro-2-nitrobenzene. The method for determining 2-nitroanisole has been recorded in the form of an analytical procedure (see Appendix). This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.